Q. My teen has promised she would quit smoking pot. I want to start testing her. How many days should I wait until I test her for the first time to achieve a negative test result?

A. The technical part of your question is not difficult; a urine test for cannabis can remain positive for several weeks after marijuana useage. So the presence of the drug in a urine sample will not distinguish between current use and that occurring several weeks beforehand. In addition to the testing issue, it would be good to have your child participate in some drug education programs. Perhaps this is done through the school, but other resources are available as well.

http://www.acde.org/

http://165.112.78.61/DrugPages/Marijuana.html

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